Foreword i
What’s new ii
Introduction iii
Definitions v
A. Infection control 1
1. What is infection control? 1
2. Legislative frameworks 3
3. Duty of care 3
4. Treating patients with blood-borne viral infections 5
5. Infected dental practitioners 5
B. Standard precautions of infection control 6
1. Hand hygiene 6
Hand care 7
2. Personal protective equipment 7
Gloves 7
Masks 8
Eye protection 8
Protective clothing 9
Footwear 9
3. Surgical procedures and aseptic technique 9
4. Management of sharps 9
Disposal of sharps 10
5. Management of clinical waste 10
6. Environment 11
Design of premises 11
Cleaning the environment 11
Treatment areas 12
C. Infection control strategies within the contaminated zone 13
1. Clean and contaminated zones 13
2. Waterlines and water quality 14
Water quality 14
3. Single-use items 14
4. Matrix bands 15
5. Burs 15
6. Implant drills 15
Contents
D. Instrument reprocessing 16
1. Categories of instruments: infection risk relative to instrument use 16
2. Instrument reprocessing area and workflow 17
Design of reprocessing area 17
3. Transfer of contaminated instruments and sharps 18
4. Cleaning 18
Manual cleaning 19
Mechanical cleaning 19
Drying instruments 19
5. Packaging prior to steam sterilisation 20
6. Batch Control Identification (BCI) 20
7. Steam sterilisation 22
8. Maintenance and testing 22
Validation of the sterilisation process 22
Monitoring of cycles 23
Operating the steam steriliser 23
9. Steam steriliser performance tests 23
Loading 23
Drying 24
Checking the completed load 24
Retention of hard copy printouts from steam sterilisers 24
10. Steam steriliser monitoring tests 24
Chemical indicators 24
Storage of chemical indicators 25
Biological indicators 26
11. Disinfection 26
Thermal disinfection using washer-disinfectors 26
Chemical disinfection using instrument disinfectants – high level 26
12. Storage of processed instruments 26
User checks to be made before using instruments 27
Unwrapped semi-critical and non-critical items 27
E. Documentation and practice protocols for infection control 28
1. Maintaining sterilisation records 28
2. Infection control for dental practitioners and clinical support staff 29
Immunisation 29
Immunisation records 29
Education 30
3. Exposure incident protocol 30
4. Infection control manual and other practice management issues 30
Infection control manual 31
F. Special areas and their particular dental infection control requirements 32
1. Dental radiology and photography 32
2. Specialised intraoral equipment and devices 32
Curing light 33
Air abrasion, electrosurgery units and lasers 34
3. Implants 34
4. Impressions 34
5. Dental laboratory and dental prosthetics 34
6. Handpiece management 35
7. Specimens 35
8. Endodontic irrigants 35
9. Gutta percha points 36
10. Hand operated endodontic files 36
11. Nickel-titanium (NiTi) endodontic files 36
Cleaning rotary endodontic files 36
12. Relative analgesia equipment 36
13. Nursing home visits 37
G. Infectious diseases, allergies and transmission-based 38
precautions for infection control
1. Prion diseases including Creutzfeldt-Jakob disease (CJD) 38
2. Measles, mumps, tuberculosis 38
3. Staphylococcus aureus (MRSA) 38
4. H5N1 avian influenza 39
5. Human infections with avian influenza A (H7N9) viruses 39
6. Allergies to chlorhexidine 39
7. Latex sensitivity 40
8. Blood-borne viruses and the infected dental practitioner 40
9. Exposure prevention methods and exposure prone techniques 40
Appendix 41
Blood and body fluid exposure protocol 41
Additional reading 44
Guidelines for Infection Control | Page i
Foreword
This third edition of the ADA’s Guidelines for Infection
Control incorporates a number of changes that have arisen
since the publication of the second edition in 2012, including
the release in December 2014 of the revised AS/NZS 4187.
It is the intention of the Australian Dental Association (ADA)
that these infection control guidelines will continue to be
updated every three years to ensure they remain aligned to
the evidence base of infection control.
This current edition of the ADA’s Guidelines for Infection
Control is the result of over 25 years dedicated work by
the members of the ADA’s Infection Control Committee.
During that time the Committee has assisted external
expert bodies such as the National Health and Medical
Research Council (NHMRC) and the Communicable Diseases
Network of Australia (CDNA) to help define safe practise.
Quite fittingly, the ADA’s Guidelines for Infection Control
are now recognised as a key source of information for
the NHMRC Guidelines, and have been identified by the
Dental Board of Australia as a mandatory resource for
dental practitioners.
The production of this document has required a
considerable effort over a long period. Special thanks and
acknowledgment are due to the Editor of the second and
third edition of the Guidelines (Professor Laurence Walsh)
and to current and former members of the ADA’s Infection
Control Committee (currently chaired by Dr Sharon Liberali),
for their generous donation of time and their technical
advice and expertise in preparing this document.
The ADA declares that no conflict of interest existed in the
development of these guidelines, and that they have been
developed independently without any corporate interest or
sponsorship.
Rick Olive
President
Australian Dental Association
Page ii | Guidelines for Infection Control
What’s new
This third edition of the ADA’s Guidelines for Infection
Control contains a significant number of additions to the
second edition published in 2012.
These changes are a direct result of the ADA’s commitment
to remaining aligned with current international best practice
in evidence-based infection control.
They are also a consequence of revisions to the two main
standards relevant to instrument processing in Australian
dental practices, AS/NZS 4815 and AS/ANZ 4187,
both of which are considered key resources in the
formulation of the Dental Board of Australia Guidelines
on Infection Control, and hence in the creation of
this document.
Registered dental practitioners are legally required to comply
with all of the Dental Board of Australia’s policies and
guidelines, which includes ensuring that mandatory infection
control guidelines are instituted in full in their practices.
This is an obligation that cannot be delegated.
It’s important that every registered dental practitioner
familiarise themselves with every new element of infection
control practice included in this document and incorporate
them into their practice’s infection control manual.
Please note that all new additional information is
highlighted in pale blue for your convenience.
Guidelines for Infection Control | Page iii
Introduction
The ADA’s Guidelines for Infection Control describes
the infection control procedures dental practitioners and
their clinical support staff are expected to follow in a dental
practice. It outlines the primary responsibilities of dental
practitioners in relation to infection control, and provides
the rationale for those obligations. Greater details on
key aspects are provided in the companion resource,
the ADA’s Practical Guide to Infection Control.
The routine work practises outlined in the ADA’s Guidelines
for Infection Control are designed to reduce the number
of infectious agents in the dental practice environment;
prevent or reduce the likelihood of transmission of these
infectious agents from one person or item/location to
another; and make items and areas as free as possible
from infectious agents. It is important to acknowledge
that professional judgement is essential in determining
the application of these guidelines to the situation of the
individual dental practice environment. Individual dental
practices must have their own infection control procedures
in place, which are tailored to their particular daily routines.
Professional judgement is critical when applying these
guidelines to the particular circumstances of each individual
dental practice.
The Dental Board of Australia’s Guidelines on Infection
Control address how dental practitioners can prevent or
minimise the risk of the spread of infection in the dental
setting. There are two critical parts to these guidelines –
documentation and behaviours.
All dental practitioners when they apply for or renew their
registration undertake to comply with all relevant legislation,
and the Dental Board of Australia registration standards,
codes and guidelines – this includes the Board’s Guidelines
on Infection Control. These requirements apply to all
dental practitioners, be they an employee or employer.
Failure to comply with these guidelines may lead to a
practitioner’s conduct being investigated by the Board.
All clinical support staff require appropriate training in
the infection control measures they are expected to
undertake everyday. Compliance with procedures is more
likely if those involved in carrying them out understand
the rationale behind the requirements. This includes
knowing how infections are transmitted; what personal
protection is needed and when and how to use it correctly;
what vaccinations are needed and why; details of how to
keep the practice clean and hygienic and what to do in the
event of an exposure incident such as a skin penetrating
injury with a sharp instrument. Effective infection control
involves not only maintaining documentation about the
various procedures and processes in a specific manual,
but reviewing protocols, training and documentation on a
regular basis, and ensuring staff members undertake the
procedures in a consistent and uniform manner.
Supporting and reference documents
These guidelines are mainly evidence-based or otherwise
based on current international best practice, and have
been drawn from current expert knowledge and advice
in infection control. These guidelines will be regularly
reviewed and updated in light of changes in the knowledge
base. References used to prepare these guidelines are listed
at the footer of each page in which they are cited and can
be sourced for further information. Practitioners should
also refer to the NHMRC Australian Guidelines for the
Prevention and Control of Infection in Healthcare. The
NHMRC Guidelines should be regarded as a companion
document to the ADA’s Guidelines for Infection Control
as it addresses the foundations of infection control across all
healthcare settings, including dental practice, and provides
specific advice on situations where additional risk-based
precautions are warranted.
Two standards from Standards Australia are relevant
to instrument reprocessing in dental practice, namely
AS/NZS 4815 and AS/NZS 4187. Both documents are
identified as key resources in the Dental Board of Australia’s
Guidelines on Infection Control.
The Australian and New Zealand Standard AS/NZS 4815
Office-based health care facilities – Reprocessing
of reusable medical and surgical instruments and
equipment, and maintenance of the associated
environment is relevant to office-based dental practice.
Public dental clinics and large facilities would generally
operate under AS/NZS 4187 Cleaning, disinfecting and
sterilising reusable medical and surgical instruments
and equipment, and maintenance of associated
environments in health care facilities.
AS/NZS 4187 was updated in 2014, while the former
document remains current, and is subject to a proposal
for revision to maintain it as a contemporary and relevant
document into the future.The 2014 update of AS/NZS
4187 and future revision of AS/NZS 4815 take into account
international standards and global guidelines, such as those
from the International Organization for Standardization
(ISO). As a result the newly revised AS/NZS 4187 is written
in a different format from the previous 2003 version. Future
editions of the ADA’s Guidelines for Infection Control
will take into account points raised following the revision of
AS/NZS 4815.
Each dental practitioner is responsible for
implementing these guidelines in their clinical
practice and for ensuring their clinical support
staff are familiar with and able to apply them.
Therefore, each dental practitioner must ensure
that they and their staff fulfil their obligations to
practise in a safe and hygienic manner. The individual
practitioner is responsible for ensuring compliance
with infection control requirements throughout the
practice. This cannot be delegated.
Page iv | Guidelines for Infection Control
AS or AS/NZS refers to the Australian and New Zealand
standards, authored by SAI Global. These are referred to
as either AS or AS/NZS followed by the relevant standard
number.
Blood-borne viruses (BBVs) include hepatitis B (HBV),
hepatitis C (HCV) and human immunodeficiency (HIV).
These viruses are transmitted primarily by blood-to-blood
contact.
Clinical support staff members are those staff other than
registered dental practitioners who assist in the provision of
dental services – namely dental chairside assistants, dental
laboratory assistants and dental technicians.
Contaminated zone is that area of work in which
contamination by patient fluids (blood and saliva) may occur
by transfer, splashing or splatter of material. It includes
the operating field in the dental operatory, as well as
the instrument cleaning area within the sterilising room.
Contamination must be confined and contained to this area.
Dental Board refers to the Dental Board of Australia.
Dental practitioners is an inclusive term that refers to
those registered by the Dental Board to provide clinical
dental care to patients, and comprises dentists, dental
specialists, dental prosthetists, dental therapists, dental
hygienists, and oral health therapists.
Dental staff is an inclusive term for all those employed in a
dental practice setting – namely dental practitioners, clinical
support staff and clerical or administrative staff.
Disinfection is the destruction of pathogenic and other
kinds of microorganisms by physical or chemical means.
Exposure incident is any incident where a contaminated
object or substance breaches the integrity of the skin or
mucous membranes or comes into contact with the eyes.
Exposure prone procedures (EPPs) are procedures where
there is a risk of injury to dental staff resulting in exposure of
the patient’s open tissues to the blood of the staff member.
These procedures include those where the dental staff’s
hands (whether gloved or not) may be in contact with sharp
instruments, needle tips or sharp tissues (spicules of bone or
teeth) inside a patient’s open body cavity, wound or confined
anatomical space where the hands or fingertips may not be
completely visible at all times. Three different types of EPPs
are described in the CDNA Australian National Guidelines
for the Management of Health Care Workers known to
be Infected with Blood-Borne Viruses.
Category 1
The majority of procedures in dentistry are Category 1 EPPs
because they are undertaken with the hands and fingertips
of the dental practitioner visible and outside the mouth.
1
From section B5.3 of the NHMRC 2010 Australian Guidelines for the Prevention and Control of Infection in Healthcare and Appendix 1 of
the CDNA Australian National Guidelines for the Management of Health Care Workers known to be infected with Blood-Borne Viruses.
The possibility of injury to the practitioner’s gloved hands
from sharp instruments and/or tissues is slight, and the
risk is remote of the practitioner bleeding into a patient’s
open tissues. The possibility of injury to the practitioner’s
gloved hands from sharp instruments and/or tissues is slight,
and the risk of the practitioner bleeding into a patient’s open
tissues is remote.
Category 2
In a smaller group of procedures, designated as Category 2
EPPs, the fingertips may not be visible at all times; however,
injury is unlikely to occur to the practitioner’s gloved hands
from sharp instruments and/or tissues. If injury occurs it
is likely to be noticed and acted upon quickly to avoid the
dental practitioner’s blood contaminating a patient’s open
tissues.
Category 3
Category 3 EPPs in dentistry are surgical procedures where
the fingertips are out of sight for a significant part of
the procedure, or during certain critical stages in which
there is a distinct risk of injury to the dental practitioner’s
gloved hands from sharp instruments and/or tissues.
In such circumstances, it is possible exposure of the patient’s
open tissues to the practitioner’s blood may go unnoticed
or would not be noticed immediately. Such procedures
include: maxillofacial surgery; oral surgical procedures
including surgical removal of teeth and dento-alveolar
surgery; periodontal surgical procedures; endodontic
surgical procedures; and implant surgical procedures
(such as implant placement and recovery). The definition
of Category 3 EPPs excludes forceps extraction of highly
mobile or exfoliating teeth.
Invasive procedure is any procedure that pierces skin
or mucous membrane or enters a body cavity or organ.
This includes surgical entry into tissues, cavities or organs,
or repair of traumatic injuries to the soft tissues.
Penetrating injury is any injury from a sharp object such
as an injection needle, scalpel blade, dental bur or denture
clasp contaminated with a patient’s blood or saliva.
Surgical procedure is one where there is a planned breach
of a patient’s skin or mucosa and penetration into deeper
layers of tissue which have a different immune response.1
Traceability is a protocol that requires a record of the
distribution and location of each individual instrument during
use and after each sterilisation cycle and during storage,
e.g. using laser engraving of individual instruments.
Note: this is different from batch control identification
(previously termed tracking) which links a sterilising cycle to
a package of instruments used on a patient.
Definitions
Guidelines for Infection Control | Page 1
1. What is infection control?
The purpose of infection control in dental practice is to
prevent the transmission of disease-producing agents such
as bacteria, viruses and fungi from one patient to another,
from dental practitioner and dental staff to patients, and
from patients to dental practitioner or other dental staff. In
addition, it is necessary that endogenous spread of infection
is also prevented by limiting the spread of infectious agents.
In dental practice, microorganisms may be inhaled,
implanted, ingested, injected, or splashed onto the skin
or mucosa. They can spread by direct contact from
one person to another, or through indirect contact via
instruments and equipment, when the dental staff member’s
hands or clothing become contaminated, where patient-
care devices are shared between patients, when infectious
patients have contact with other patients, or where
environmental surfaces are not regularly decontaminated.
In the dental practice setting, microorganisms can also
spread by airborne transmission – when dental staff or
others inhale small particles containing infectious agents.
A number of infectious agents, including viral influenza,
can be transmitted through respiratory droplets (i.e. large-
particle droplets > 5 microns in size) generated by a patient
who is coughing, sneezing or talking. Transmission via large
droplets (splash and splatter) requires close contact, as large
droplets do not remain suspended in the air.
A. Infection control
Droplet transmission can occur when a staff member’s
hands become contaminated with respiratory droplets and
transferred to susceptible mucosal surfaces such as the eyes,
when infectious respiratory droplets are expelled by coughing,
sneezing or talking and come into contact with another
person’s mucosa (eyes, nose or mouth), either directly into or
via contaminated hands.
There is good evidence viral influenza and certain other
respiratory infections can spread via aerosols as well as
by droplets. This has implications in terms of how close items,
such as open boxes of gloves, are positioned in relation to
possible sources of contamination, such as the patient’s
mouth or the instrument washing sink of the sterilising room.
Since concentrations of pathogens in aerosols decrease with
increasing distance from the patient’s mouth,2
a distance of
1.829 m (6 feet) has been recommended for medical staff
examining patients with suspected influenza. This distance
serves as a useful evidence-based measure in terms of how
far open glove boxes should be from the patient’s mouth to
minimise the likelihood of aerosol contamination.
Whether or not the spread of microorganisms results
in clinical infection depends in part on the virulence
(power to infect) of a particular microorganism and on the
susceptibility of the host. For instance, hepatitis B virus
(HBV) is highly infectious and the chance that this disease
will be transmitted by a contaminated penetrating injury
to a non-immune person is approximately one in three
(depending on the infective status of the source of injury).
In comparison, the chance of transmission of the hepatitis C
virus (HCV) by similar means is one in 30; and for HIV/AIDS,
one in 300. Patients and dental staff have varying
susceptibilities to infection depending on their age,
state of health, underlying illnesses, and immune status
(which may be impaired by medication, disease, cancer
therapy and other factors such as malnutrition and
hormone deficiency).
Infection control focuses on limiting or controlling factors
influencing the transmission of infection or contribute to the
spread of microorganisms. The spread of microorganisms can
be reduced by:
• limiting surface contamination by microorganisms;
• adhering to good personal hygiene practices,
particularly efficient hand hygiene;
• using personal protective equipment;
• using disposable products where appropriate (e.g.
paper towels); and
• following risk minimisation techniques such as using
rubber dam and pre-procedural mouthrinsing.
2
Bischoff WE, Swett K, Leng I, Peters TR. Exposure to influenza virus aerosols during routine patient care. J Infect Dis, 2013;207:1037-1046.
Successful infection control involves:
• understanding the basic principles of infection
control;
• creating systems that allow infection control
procedures to be implemented effectively and
make compliance with them easy (this includes
having clear procedural documentation, and
comprehensive training of dental staff together
with a process of regular monitoring of the
application of these systems and procedures);
• keeping up-to-date regarding specific infectious
diseases, particularly newly-evolving infection
challenges such as avian (H5N1 or H7N9)
influenza, emerging human influenza viruses,
and multiple resistant organisms, and how to
take precautions against them; and
• identifying settings that need modified
procedures (e.g. nursing homes).
Page 2 | Guidelines for Infection Control
Standard precautions are the basic processes of infection
control to minimise the risk of transmission of infection
and include:
• undertaking regular hand hygiene before gloving
and after glove removal;
• using personal protective barriers such as gloves,
masks, eye protection and gowns;
• wearing appropriate protective equipment during
clinical procedures and when cleaning and
reprocessing instruments;
• correctly handling contaminated waste;
• appropriately handling sharps;
• appropriately reprocessing reusable instruments;
• effectively undertaking environmental cleaning;
• respiratory hygiene and cough etiquette;
• using aseptic non-touch techniques where indicated;
• appropriately handling used linen and clinical
gowns; and
• using, where appropriate, environmental barriers
such as plastic coverings on surfaces and items that
may become contaminated and are difficult to clean.
These standard precautions minimise the risk of transmission
of infection from person to person, and are required for
the treatment of all dental patients regardless of whether
a particular patient is infected with or is a carrier of an
infectious disease. They apply to all situations whenever
dental practitioners or their clinical support staff touch
the mucous membranes or non-intact skin of a dental
patient. Standard precautions are also essential when
cleaning the dental surgery environment, when handling
items contaminated with saliva (e.g. radiographs, dentures,
orthodontic appliances, wax rims and other prosthetic
work that have been in a patient’s mouth), when handling
blood (including dried blood), saliva and other body fluids
(excluding sweat) whether containing visible blood or not,
and when cleaning and processing instruments.
There are a number of situations where patients have a
specific highly infectious condition that necessitates the use
of transmission-based precautions in addition to standard
precautions, to address the increased risk of transmission.
Transmission-based (risk-based) precautions are applied
to patients suspected or confirmed to be infected with
agents transmitted by the contact, droplet or airborne
routes. The agents of most concern to dental practise are
respiratory viruses.
The range of measures used in transmission-based
precautions depends on the route(s) of transmission of the
infectious agent. The application of transmission-based
precautions is particularly important in containing multi-
resistant organisms (MROs) in hospital environments and in
the management of outbreaks of norovirus gastroenteritis in
institutions such as hospitals and nursing homes.
The requirements for transmission-based precautions
are listed in the NHMRC Guidelines. In brief, contact
precautions are used when there is a risk of direct or indirect
contact transmission of infectious agents (e.g. MRSA,
Clostridium difficile, or highly contagious skin infections/
infestations) that are not effectively contained by standard
precautions.
Droplet precautions are intended to prevent transmission
of infectious agents spread through respiratory or mucous
membrane contact with respiratory secretions. Positive
pressure ventilation is not required as these microorganisms
do not travel over long distances in droplets or aerosols.
Airborne precautions, such as wearing P2 (N95) surgical
respirators, are designed to reduce the likelihood of
transmission of microorganisms that remain infectious over
time and distance when suspended in the air. These agents
may be inhaled by susceptible individuals who have not
had face-to-face contact with (or been in the same room as)
the infectious individual. Infectious agents for which airborne
precautions are indicated include measles, chickenpox
(varicella) and Mycobacterium tuberculosis. At present
there is a lack of evidence from clinical trials regarding the
additional benefit of P2 (N95) respirators over conventional
surgical masks for reducing the risk of transmission of viral
influenza. A mask tightly sealed to the face has been shown
to block entry of 95% of total influenza virus particles,
while a tightly sealed N95 surgical respirator can block over
99% of virus particles. In contrast, a loosely fitted mask
blocks 56% and a poorly fitted respirator only 66% of
infectious virus particles.3
In other words, a poorly fitted
N95 surgical respirator performs no better than a loosely
fitting surgical mask.
The majority of procedures undertaken in dentistry generate
aerosols. Therefore, it is important to recognise that
patients with active tuberculosis, measles, chickenpox or
viral influenza pose a considerable risk to dental staff and
patients if they undergo dental treatment. Patients for whom
airborne precautions are indicated, formal risk assessment
should be undertaken to determine the need for dental
treatment.
Non-urgent treatment should be delayed or postponed.
If patients require urgent care, transmission-based
precautions must be followed.
3
Noti JD, Lindsley WG, Blachere FM, Cao G, Kashon ML, Thewlis RE, et.al. Detection of infectious influenza virus in cough aerosols generated in a
simulated patient examination room. Clin Infect Dis. 2012;54:1569-1577.
Guidelines for Infection Control | Page 3
Additional measures would include patients being seen
as the last patients of the day. Use of pre-procedural
mouthrinses and rubber dam is essential, together with
minimising the use of aerosol-generating techniques, and
two cycles of cleaning for environmental surfaces. In general,
there will be few situations where the use of analgesics and
appropriate antimicrobial agents will not allow a delay until
the patient is no longer infectious.
2. Legislative frameworks
Registered dental practitioners are legally required to
comply with the Dental Board of Australia’s policies and
guidelines. This responsibility cannot be delegated to the
dental assistants or practice manager or practice owner.
Rather, each registrant must ensure they fulfil the obligations
to practise in a safe and hygienic manner.
In the area of infection control, the Dental Board stipulates
the expectations for infection control are based on the
current edition of the ADA’s Guidelines for Infection
Control and NHMRC Guidelines, plus current versions
of either AS/NZS 4815 or AS/NZS 4187 for instrument
reprocessing.
It is essential for staff members to understand the infection
control policies of a dental practice reflect these legislative
requirements, as well as other obligations of law including
work health and safety legislation, which stipulates
the need to follow legal directions including written
safety instructions or directives from the employer (a term
which includes compliance with infection control protocols).
Such directives can be shown to be reasonable by reference
to the current ADA’s Guidelines for Infection Control.
3. Duty of care
Dental practitioners have a common law legal duty of
care to their patients, and must ensure that effective
infection control measures are in place and are complied
with in the practice.
The Dental Board stipulates that dental practitioners must
practise in a way that maintains and enhances public
health and safety by ensuring that the risk of the spread
of infectious diseases is prevented or minimised.4
Dental
practitioners must ensure the premises in which they
practise are kept in a clean and hygienic state to prevent or
minimise the spread of infectious diseases; and ensure that,
in attending a patient, they take such steps as are practicable
to prevent or minimise the spread of infectious diseases.
Consequently, all dental practitioners and clinical support
staff have a responsibility to follow the specific infection
control policies in their place of work.
4
See the Dental Board of Australia Guidelines on Infection Control, July 2010 http://www.dentalboard.gov.au/Codes-and-Guidelines.aspx
For all staff members, there are also duties of care to the
person themselves and to others (in this case other workers
and patients of the practice whose health and safety would
be compromised by the staff member not following correct
procedures). Compliance of staff members with workplace
protocols should be a key element of the assessment of
their performance.
Staff members who repeatedly demonstrate poor
compliance with infection control expectations should be
given both verbal warnings in private as well as written
warnings, and be reminded of the points above and their
need to follow lawful safety directives, as this will be very
useful in the event of a later charge of unfair dismissal.
Jurisdictional work health and safety laws are framed
in such a way as to empower employers in the situation
where an employee has shown wilful disregard of the
required safe working procedures.
Page 4 | Guidelines for Infection Control
Dental practitioners must:
• develop and implement work practises to ensure compliance with infection control standards;
• document their infection control protocols in an infection control manual;
• ensure that all dental staff have read the infection control manual and have been trained in the infection
control protocols used in the practice;
• provide their dental staff with access to key resources such as these Guidelines, the NHMRC Guidelines,
and AS/NZS 4815 or AS/NZS 4187;
• have in place a system of reporting, monitoring and rectifying breaches of infection control protocols
(which would involve addressing this topic in staff meetings and recording the outcomes from
such discussions);
• ensure an immunisation programme for dental staff is in place and is in accordance with the current
edition of the Australian Immunisation Handbook;
• maintain a vaccination record for each member of the dental staff (see Section E. for a list of
recommended immunisations);
• maintain a record of workplace incidents and accidents (including sharps injuries) as required by
national WHS legislation;
• maintain an allergy record for each member of the dental staff;
• implement specific training and education on personal protective equipment;
• implement a hand hygiene programme consistent with the national hand hygiene initiative from
Hand Hygiene Australia (HHA) which promotes the use of alcohol-based hand rubs in situations where
hands are not visibly contaminated;
• implement systems for the safe handling and disposal of sharps;
• implement systems to prevent and manage occupational exposure to blood-borne viruses;
• implement systems for environmental cleaning;
• implement systems for processing of reusable instruments and devices;
• be aware of their immune status. The Dental Board stipulates that all dental practitioners must be
aware of their infectious status for the blood-borne viruses HBV, HCV and HIV, seek expert medical
advice from an infectious diseases specialist familiar with the requirements of dental practice or from an
expert advisory panel if diagnosed with a blood-borne virus. Such advice could include a prohibition on
undertaking exposure prone procedures (EPPs) if viraemic; and
• follow through after potential exposures to blood-borne viruses, including reporting the incident if it
was an occupational exposure, undergoing testing, and if necessary, seek specialist medical management.
Note: it is not necessary for practitioners to stop performing EPPs after the exposure, unless they are found to
have become infected with the blood-borne virus.
Guidelines for Infection Control | Page 5
5
Anti-discrimination, privacy, industrial relations and equal opportunity laws apply. Relevant state, territory and commonwealth legislation is listed
in the References and Additional Reading.
Under work health and safety legislation, practice owners
have an obligation to provide and maintain a safe working
environment for employees and for members of the public.
This means practice owners must provide their employed
dental practitioners and dental staff with the required
materials and equipment to allow these employees to fulfil
their legal obligations for implementing effective infection
control in their workplace.
The law demands that dental practitioners take reasonable
steps to accommodate a patient’s disability. It is a breach
of anti-discrimination laws for dental practitioners to refuse
to treat or impose extra conditions on a patient who has a
disability such as being infected with or being a carrier of a
blood-borne virus.5
4. Treating patients with blood-borne viral
infections
5. Infected dental practitioners
All dental practitioners when applying for or renewing their
registration undertake to comply with all relevant legislation,
Dental Board registration standards, codes and guidelines –
this includes the Dental Board of Australia’s Guidelines on
Infection Control.
They also declare that they are aware of their infection
status for blood-borne viruses and will comply with the
Communicable Diseases Network Australia’s (CDNA)
Australian National Guidelines for the Management
of Health Care Workers known to be Infected with
Blood-Borne Viruses and with the requirements of the
Dental Board’s Guidelines on Infection Control in relation
to blood-borne viruses.
They must follow the advice of their treating medical
practitioner and any additional stipulations of jurisdictional
public health authorities. If a dental practitioner knows
or suspects they have been infected with a blood-borne
virus, they should consult an appropriately experienced
medical practitioner or infectious disease specialist familiar
with the requirements of dental practice. This includes
seeking treatment, modifying their clinical practice where
appropriate, which may include not performing EPPs,
in accordance with the relevant policies and guidelines of
the Dental Board and the current CDNA National Guidelines.
It is not appropriate for a practitioner to rely on their own
assessment of the risk that they pose to patients.
While the protection of the public’s health is paramount,
employers of dental practitioners should also consider, and
comply with, relevant anti-discrimination, privacy, industrial
relations and equal employment opportunity legislation.
Employers must ensure the status and rights of infected staff
members as employees are safeguarded.
The Dental Board’s Guidelines on Infection Control
state that practitioners are required to make a declaration
that they are aware of their blood-borne virus status and
that they will comply with the CDNA National Guidelines
as well the requirements of the Dental Board’s Guidelines
on Infection Control. This policy also applies to registered
dental students.
The CDNA National Guidelines set the requirements
in relation to the management of healthcare workers
including dental practitioners with blood-borne viruses
and any restrictions in the performance of exposure-
prone procedures. It is essential that dental practitioners
be aware of and comply with the most current version of
these guidelines which may change as new evidence in
the management of healthcare workers with blood-borne
viruses emerges.
Risks of transmission from an infected clinician to a patient
are dependent on a range of factors including the infectivity
of the source clinician (e.g. viral load and effect of viral
treatments), the clinical treatment type, and operator
skill and experience. Effective anti-viral drug treatment
protocols reduce the infectivity of individuals, and persistent
negative results may result in a review of the infectious
status of the practitioner. This may influence whether or
not the practitioner may perform EPPs. The CDNA National
Guidelines recommend regular testing for blood-borne
viruses for the duration of the practitioner’s career, to ensure
virus levels remain undetectable.
Patients with hepatitis B, C or HIV are treated using
standard precautions and the same cleaning and
sterilisation techniques as for other patients. It is important
for dental practitioners and their staff to feel assured
that their infection control procedures are adequate for
all patients – whether patients carry blood-borne viral
infections or not. Patients should not want to hide their
infectious status because of the way the staff act in their
presence – and those providing their care want to know
about these conditions for other reasons, so that care can
be provided safely and effectively.
The Dental Board requires registered dental practitioners to
comply with the CDNA Australian National Guidelines
for the Management of Health Care Workers known
to be Infected with a Blood-borne Viruses (CDNA
National Guidelines), irrespective of what local ‘workplace’
guidelines are in place.
Page 6 | Guidelines for Infection Control
6
http://apps.who.int/iris/bitstream/10665/78060/1/9789241503372_eng.pdf and
http://whqlibdoc.who.int/publications/2009/9789241597906_eng.pdf
The following standard precautions form the basis of
infection control and must be carried out routinely for
all patients.
1. Hand hygiene
Hand hygiene is a general term applying to processes
aiming to reduce the number of microorganisms on
hands. This includes either the application of a waterless
antimicrobial agent, e.g. alcohol-based hand rub (ABHR), to
the surface of the hands, or the use of soap/solution (plain
or antimicrobial) and water, followed by patting dry with
single-use towels.
Comprehensive information on contemporary hand hygiene
measures is found on the Hand Hygiene Australia (HHA)
website www.hha.org.au.
The HHA protocol is to use an ABHR for all clinical situations
where hands are visibly clean. The normal routine in dental
practice should be for dental staff to use ABHR between
patient appointments and during interruptions within the
one appointment. ABHR is applied onto dry hands and
rubbed on for 15-20 seconds, after which time the hands
will be dry.
ABHR can be used as often as is required. However,
a compatible moisturiser should be applied up to four
times per day. ABHR must only be used on dry skin;
wet hands dilutes the product thus decreasing its
effectiveness. Unlike detergents, ABHRs do not remove
skin lipids and they do not require paper towel for drying.
A range of ABHR products are registered with Therapeutic
Goods Administration (TGA). These contain a sufficiently
high level of alcohol (ethanol or isopropanol) to achieve the
desired level of decontamination. Practitioners must not use
ABHR products that do not carry TGA approval. Typically,
suitable ABHR will contain a skin emollient to minimise the
risk of skin irritation and drying, have minimal colour and
fragrance, and will leave the hands in a dry state after being
rubbed in for 15-20 seconds.
Bottles of ABHR should not be ‘topped up’ because the
outside of the dispenser may become contaminated. Empty
dispensers should be discarded and not reused. To date,
attempts to recycle/reuse ABHR dispensers have proven not
be to cost effective in Australia.
Staff with an existing skin irritation may experience a
stinging sensation when first using ABHR. This usually
subsides over several weeks with the ongoing use of an
emollient-containing ABHR. However, medical advice should
be sought if symptoms persist.
Dental staff must be educated on the correct use of ABHR
and handwashing products, and caring for their hands.
Regular use of skin moisturisers both at work and at home
should be promoted. Moisturising skin care products used in
the dental practice must be compatible with the ABHR.
For further information on hand decontamination with
ABHR, see www.hha.org.au. This site also has posters on
‘How to Hand Rub’ and ‘How to Handwash’ which can be
downloaded for use in dental practice.
Hands must always be washed at the start of a working
session, after toilet breaks, and when leaving the surgery.
They must be washed with soap and water when visibly dirty
or contaminated with proteinaceous material, or visibly soiled
with blood or other body fluids. Washing hands with soap
and water is preferred in these situations as it guarantees a
mechanical removal effect.
Washing hands with soap and water immediately before
or after using an ABHR is not only unnecessary, but may
lead to dermatitis. For this reason, it is both desirable and
convenient to position ABHR dispensers close to the clinical
working area (but away from contamination by splash and
aerosols), rather than at an existing handwashing sink.
Handwashing should be undertaken in dedicated (clean)
sinks preferably fitted with non-touch taps (or carried out
using a non-touch technique) and not in the (contaminated)
sinks used for instrument cleaning.
B. Standard precautions of infection control
Hand hygiene is required after removal of gloves. This must
be done before the dental practitioner writes or types up
patient notes. Hand gel is used again immediately before
gloving for the next patient.
If handshaking occurs, either at the start or end of an
appointment, it may increase the risk of transmission
of skin-borne pathogens.6
This risk can be mitigated
by undertaking additional hand hygiene after shaking
hands. Practitioners should not shake a patient’s hand
when greeting them in the reception without having first
completed hand hygiene.
Both alcohol-based gels and solutions are available with
proven efficacy designed for use in healthcare settings.
ABHR products designed for domestic use lack TGA
registration. As a result, domestic products must not be
used in clinical settings. Only a limited number of alcohol-
containing foams are certified for use for hand hygiene in
healthcare settings. Particular attention to handwashing
is required when dental practitioners work outside the
normal clinical environment, e.g. in a nursing home or at
a patient’s home, since ABHR products do not inactivate
norovirus, hepatitis B and certain other enteric viruses
which spread readily from contact with contaminated
surfaces.
Guidelines for Infection Control | Page 7
If touch taps are used, the taps may be turned on and off
with a paper towel.
Hand hygiene must be undertaken before and after contact
with every patient, before gloves are put on and after they
are removed. If hands are washed, wet hands must be dried
with single-use linen or disposable paper towels.
Hand care
Hands must be well cared for, because intact skin is a first
line defence mechanism against infection. Damaged skin
can lead to infection in the host as well as harbour higher
numbers of microorganisms than intact skin, increasing
the risk of transmission to others. Damaged skin in dental
practitioners and clinical support staff is an important
issue because of the high frequency of dry, itchy skin from
irritant contact dermatitis, primarily caused by frequent
and repeated use of handwashing products – especially
soaps, other detergents, and paper towel use, resulting in
drying skin. Other factors that may contribute to dermatitis
include fragrances and preservatives in hand care products
(which can cause contact allergies), donning gloves while
hands are still wet, using hot water for handwashing, failing
to use moisturisers and using poor quality paper towels.
Lacerated, chafed or cracked skin can allow entry of
microorganisms, any cuts or open wounds need to be
covered with a waterproof dressing. All hand, wrist or
nail jewellery, (e.g. rings, wrist watches and bracelets) must
be removed prior to putting on gloves as their presence
compromises the fit and integrity of gloves and promotes
significant growth of skin microorganisms.
A plain band ring such as a wedding ring may be left on
for non-surgical procedures but may cause irritation of the
underlying skin, in which case it should be removed.
Artificial fingernails must not be worn as they can harbour
microorganisms. Nail polish should be clear, but preferably
dental staff should not wear nail polish. All fingernails must
be kept short to prevent glove tears and to allow thorough
hand cleaning. The hands of dental staff should be free
of jewellery and false nails, with any cuts or abrasions
covered with waterproof dressings. Wrist watches are also
discouraged as they impair correct handwashing.
Further information can be found in the ADA’s Practical
Guide to Infection Control.
2. Personal protective equipment
Wearing personal protective clothing and equipment where
aerosols are likely to be generated is an important way to
reduce the risk of transmission of infectious agents. Dental
practitioners and clinical support staff must be provided with
all appropriate necessary protective clothing and equipment
for the procedure being undertaken and need to be educated
on the correct use of these items.
Barrier protection, including gloves, mask, eyewear and gown
must be removed before leaving the work area (e.g. dental
surgery, instrument processing or laboratory areas).
Gloves
Dental practitioners and clinical support staff must wear
gloves whenever there is risk of exposure to blood, saliva or
other body secretions or when hands will come in contact
with mucous membranes. This means gloves must be worn
for all clinical procedures. The infection control manual
used in the dental practice should list the protocols for
glove wearing and for hand hygiene before gloving and after
de-gloving.
Wearing gloves does not replace the need for hand hygiene
because hands may still become contaminated as a result of
manufacturing defects in new gloves that were not obvious to
the user, or because of damage (such as tears and pinpricks)
that occur to the gloves during use.
Disposable gloves used in patient care must not be washed
before or after use nor should they be reused. A new pair of
gloves must be used for each patient and changed as soon
as they are cut, torn or punctured. Gloves must be removed
or overgloves worn before touching any environmental
surface without a barrier or before accessing clean areas.
Gloves must be removed as soon as clinical treatment is
complete and hand hygiene undertaken immediately to
avoid the transfer of microorganisms to other patients or
environments.
Non-sterile examination gloves may be worn for non-surgical
general dental procedures. Gloves supplied for use in dental
practice are required to conform to AS/NZS 4011. Sterile
gloves must be worn when a sterile field is necessary for
procedures such as oral, periodontal or endodontic surgery.
Both opened and unopened boxes of gloves must be stored
away from aerosol contamination where they will not be
exposed to droplets generated by patient care. Gloves must
be worn when cleaning instruments and environmental
surfaces. The type of glove worn must be appropriate to
the task. For instance, disposable latex or nitrile gloves
are appropriate for cleaning the dental operatory during
changeover between patient appointments.
Page 8 | Guidelines for Infection Control
Heavy-duty utility, puncture-resistant gloves must be used
during manual instrument cleaning, rather than disposable
latex gloves. These utility gloves can be reused, but must be
washed in detergent after each use, stored dry and replaced
if torn, cracked, peeling or showing signs of deterioration.
It is strongly recommended to use powder-free gloves for
patient care because this reduces exposure of staff to latex
proteins via both respiratory and contact routes, thereby
minimising the risk of developing latex allergy. If the dental
practitioner, clinical support staff member or patient has a
proven or suspected allergy to latex, alternatives must be
used such as neoprene or nitrile gloves. A latex-free protocol
must also be followed including use of non-latex rubber dam,
and use of non-latex materials such as prophylaxis cups.
Note: patients with multiple food allergies have an elevated
possibility of latex allergy. It is prudent to use a latex-free
approach when treating such patients.
Further information can be found in the ADA’s Practical
Guide to Infection Control.
Masks
Dental procedures can generate large quantities of aerosols
of three microns or less in size and a number of diseases
may be transmitted via the airborne (inhalational) route.
In the dental surgery environment, the most common causes
of airborne aerosols are the high-speed air rotor handpiece,
the ultrasonic scaler and the triplex syringe. The aerosols
produced may be contaminated with bacteria and fungi from
the oral cavity (from saliva and dental biofilms),
as well as viruses from the patient’s blood.
Therefore, dental practitioners and clinical support staff
must wear suitable fluid-resistant surgical masks that block
particles of three microns or less in size. Masks protect the
mucous membranes of the nose and mouth and must be
worn wherever there is a potential for splashing, splattering
or spraying of blood, saliva or body substances, or where
there is a probability of the inhalation of aerosols with a
potential for transmission of airborne pathogens. However,
it is suggested that masks be worn at all times when treating
patients to prevent contamination of the working area with
the operator’s respiratory or nasal secretions/organisms.
The following are some basic protocols to be observed in
relation to masks as items of personal protective equipment.
Eye protection
Dental practitioners and clinical support staff must wear
protective eyewear to protect the mucous membranes of
the eyes during procedures where there is the potential for
penetrating injury or exposure to aerosols, splattering or
spraying with blood, saliva or body substances. Reusable
or disposable eyewear supplied for use in dental practice
is required to conform to AS/NZS 1337. An alternative to
protective eyewear is a face shield. However, this does not
protect from inhaled microorganisms and must be worn in
conjunction with a surgical mask.
Eyewear protects the eye from a broad range of hazards
including projectiles and should be worn for most clinical
procedures.
Protection from projectiles is particularly important during
scaling, when using rotary instruments (particularly when
removing existing restorations), cutting wires and cleaning
instruments and equipment.
Masks must:
• be put on before performing hand hygiene
and donning gloves;
• be fitted and worn according to the
manufacturer’s instructions – this means
using both tie strings where the mask has
two ties, and adapting the mask to the bridge
of the nose;
• cover both the nose and mouth, and where
possible be folded out fully to cover the chin
and upper neck; and
• be removed by touching the strings and
loops only.
Masks must not:
• be touched by the hands while being worn; or
• be worn loosely around the neck while the
dental practitioner or clinical support staff
member walks around the premises, but be
removed and discarded as soon as practical
after use.
Surgical masks for dental use are fluid-repellent paper filter
masks and are suitable for both surgical and non-surgical
dental procedures that generate aerosols. The filtration
abilities of a mask begin to decline with moisture on the
inner and outer surfaces of the mask after approximately
20 minutes.
It is difficult to change masks during long procedures
(such as surgical procedures), and is not necessary unless
the mask becomes completely wet from within or without.
Masks supplied for use in dental practice are required to
conform to AS/NZS 4381. They are required to be adapted
to the user’s face. Compared to a surgical mask with two
ties, eddy currents are more of an issue with ear loop
masks because of their poor fit, since they gape at the sides
and often around the chin.
Guidelines for Infection Control | Page 9
Eyewear must be optically clear, anti-fog, distortion-free,
close-fitting and should be shielded at the sides. Prescription
lenses are not a substitute for protective eyewear unless they
are inserted in frames designed to provide a suitable level of
protection to the orbital region.
Patients must be provided with protective eyewear to
minimise the risk of possible injury from materials or
chemicals used during treatment. Tinted lenses may protect
patients from the glare of the operating light. Spectacles
for vision do not provide sufficient protection. If patients
refuse to wear protective eyewear, the risks should be
explained and refusal noted in their dental records.
Protective clothing
Protective clothing (e.g. disposable gown), should be worn
while treating patients when it is possible aerosols or
splatter are likely to be generated or when contaminated
with blood or saliva. The most suitable type of protective
clothing and equipment used varies according to the nature
of the procedure and is a matter of professional judgement.
Where there is a risk of large splashes with blood or body
substances, impermeable protective clothing must be worn.
Disposable protective clothing items should be placed in
general waste after use, or if visibly contaminated with
blood these must be disposed of according to local waste
management regulations.
Items of protective clothing must be changed as soon as
possible when they become visibly soiled or after repeated
exposure to contaminated aerosols. The protective gown
worn in the clinical area must be removed before eating,
drinking, taking a break or leaving the practice premises.
Uniforms worn by dental practitioners and clinical support
staff must be clean and in good condition. Reusable cloth
gowns and coats can be washed in a separate washing cycle.
Footwear
Dental practitioners and clinical support staff should wear
enclosed footwear that will protect them from injury or
contact with sharp objects (e.g. accidentally dropped sharps
or spilt chemicals).
3. Surgical procedures and aseptic
technique
The principles of sterile aseptic technique must be applied
to all surgical procedures undertaken in the dental
practice setting. Sterile gloves must be used when EPPs
are undertaken such as incision into mucosal soft tissues,
surgical penetration of bone or elevation of a muco-
periosteal flap. Sterile gloves are required for the surgical
removal of teeth, for minor oral surgery procedures, for
periodontal surgery, surgical endodontics and for dental
implant placement.
In addition, these procedures include specific requirements
for surgical handwashing (using an anti-microbial
handwashing solution), gowning and gloving. Sterile gloves
supplied for use in dental practice are required to conform to
AS/NZS 4179.
4. Management of sharps
Frequently, the practice of dentistry involves the use of sharp
instruments. Occasionally, conditions of limited access and
poor visibility will increasethe risk of a penetrating injury
to dental staff and expose the patient to the blood of the
dental staff member.
Inappropriate handling of sharps, both during and after
treatment, is the major cause of penetrating injuries
involving potential exposure to blood-borne diseases in the
dental surgery.
Eyewear for patients may be either single-use or can be
reused after cleaning with detergent and water. Reuseable
protective eyewear for patients touches intact skin which is
a non-critical site. In cases where the patient has sustained
facial trauma and it is likely blood contamination of the
patient’s protective eyewear occurs, use of disposable
eyewear would be prudent as it removes the need for
complex decontamination.
The requirements for oral surgical procedures include using
sterile gloves, appropriate sterile drapes, sterile instruments,
and surgical handwashing (using an anti-microbial
handwashing solution). Long hair must be tied back and
covered and beards must also be covered.
It is important to wear sterile gloves for surgical dental
procedures (including placing dental implants), as stipulated
in the NHMRC Guidelines. Entry into sterile tissue for
removal of fully unerupted teeth, enucleation of radicular
cysts and endodontic surgery require sterile gloves.
Supplies for use during oral surgery, such as sterile cotton
pellets and gauze can be sterilised in the dental practice
using a cycle for porous loads, or purchased already sterile.
It will be uncommon for office based dental practice to
require large volumes of porous items such as dressings and
bandages. In line with AS/NZS 4815 and AS/NZS 4187 it is
recommended that goods such as dressings and bandages
be obtained sterile from commercial sources, ready for use.
Page 10 | Guidelines for Infection Control
Consequently, it is essential all sharp instruments must be
handled and used with care, and the techniques employed
to minimise the risk of penetrating injuries to dental staff.
Sharp instruments such as scalpels and scalers must never
be passed by hand between dental staff members and must
be placed in a puncture-resistant tray or bowl after each
use. Instruments and sharp items must be carried from the
surgery to the sterilising area in a lidded puncture-resistant
sharps transport container.
Needles must not be re-sheathed unless using an approved
recapping device or single-handed technique. Contaminated
needles must never be bent or broken by hand or removed
from disposable syringes. Dental practitioners are responsible
for their used needles and must develop an appropriate
management system to render them safe to ensure staff
members are not injured during patient changeover.
The dental practice must have an easily accessible, clear set
of written instructions on the appropriate action to take
in the event of an exposure incident such as a sharps injury.
These instructions must be understood and followed by all
dental staff.
Further information on the safe handling of sharps can be
found in the ADA’s Practical Guide to Infection Control.
For further information on exposure incident follow-up,
see Appendix: Blood and Body Fluid Exposure Protocol.
Disposal of sharps
The clinician using a disposable sharp item must be
responsible for its immediate safe management or
disposal after use. This must be at the point of use
(i.e. the operatory or treatment room) unless transferred
in an appropriate container.
Used disposable needle syringe combinations, empty or
partially used cartridges of local anaesthetic solution, burs,
needles, scalpel blades, orthodontic bands, endodontic
files and other single-use sharp items must be discarded
in an approved clearly labelled, puncture and leak-proof
containers.
Appropriate sharps containers are those conforming to
AS 4031 or AS/NZS 4261 as applicable.
Sharps containers must be placed in a safe position within
the treatment room to avoid accidental tipping over and
must be out of the reach of small children. Sharps containers
must be sealed when they have been filled to the line
marked on the container or when three-quarters full,
and then collected by licensed waste contractors for
disposal according to local waste management regulations.
5. Management of clinical waste
Waste in the dental practice should be separated according
to its category (medical or non-medical) at the point of
generation. Bags and containers for medical waste should
be appropriately colour coded and labelled as biohazard or
medical waste. Medical waste includes recognisable human
tissues (excluding teeth) and material or solutions containing
free-flowing blood.
Standard precautions (gloves, mask, and protective eyewear)
must be used when handling medical waste bags and
containers.
Medical waste bags and containers must not be overfilled
and must not be compacted by hand.
Medical waste and hazardous chemical waste (which
includes some chemicals and mercury used in dental
practise) must never be disposed of at local refuse tips that
use compaction of an open landfill. Medical waste and
sharps containers must be stored securely before collection
by licensed waste contractors for final disposal using
approved technologies by licensed/accredited contractors.
Extracted teeth once cleaned of visible blood, debris,
adherent soft tissues and saliva may be given to the patient.
A separate sharps container should be located in each
operatory, close to the point of use of any disposable
sharp. Disposable sharps should be placed directly into
an approved sharps container, while reusable sharps such
as burs are placed into a stand. This should be the first
step in the changeover process between patients. Dental
assistants should be trained to check that sharps such as
burs and orthodontic wires have been removed by the
operator before commencing the changeover procedure.
Burs should be removed from handpieces before removing
the handpiece from the dental unit, to reduce the risk of
sharps injury.
Disposable sharps, if not placed by the operator into a
sharps bin located at the chairside, could alternatively
be placed after use in a specific puncture-proof dish to
minimise risk. In this situation, the operating clinician has
a responsibility to minimise the risk of sharps injury when
finished with the disposable item.
Management of medical and related waste (also referred
to as contaminated waste) must conform to local state or
territory regulations. Jurisdictional Environmental Protection
Agency (EPA) regulations should be consulted for accepted
waste management protocols. In general, contaminated
waste should be held in leak-proof thick yellow bags
labelled with the biohazard symbol, and removed by a
licensed contractor. These clinical waste bags must conform
to AS/NZS 3816.
Guidelines for Infection Control | Page 11
Alternatively they can be wrapped in paper towel or placed
in a disposable cup and covered with setting plaster before
disposal in the general waste. In some states and territories
it is illegal to incinerate teeth restored with amalgam
because of issues with mercury vapour emissions, therefore
these teeth must not be placed in medical waste or into
sharps containers. Local regulations may apply on waste
management and disposal of teeth.
Information on chemical waste management for
radiography is provided in the ADA’s Practical Guide to
Infection Control.
6. Environment
A range of environmental controls can be used to reduce the
risk of transmission of infectious agents in the dental practice.
These should be considered when designing or refurbishing.
Design of premises
The design of the premises and the layout of the dental
surgery and treatment areas are important factors in
implementing successful infection control. Work areas should
be well lit and ventilated with sufficient uncluttered and easily
cleaned bench space to accommodate necessary equipment.
This is important when planning new premises or renovating
existing premises.
The clean zones of the dental practice include office areas,
staff room, waiting and reception areas as well as those
areas used for storage of supplies and sterilised instruments
and equipment. The contaminated zone is the area
contaminated with material from patient care, as well as
the instrument cleaning area. After gloving, staff may move
from the clean zone to the contaminated zone but never
the reverse direction. In the dental operatory, workflow
for instruments and materials must be from the clean zone
to the contaminated zone. Care must be taken to avoid
contaminated instruments or equipment re-entering
clean areas.
Dental assistants should put on new gloves for cleaning
working surfaces during the changeover between patients,
rather than using contaminated gloves from assisting with the
previous patient.
Floor coverings in the dental operatory must be non-slip and
impervious with sealed joins. Welded vinyl flooring is widely
used as it is long wearing and easily cleaned. Coved joints of
the flooring with the walls are preferred for ease of cleaning.
Carpet is acceptable in the waiting room but must not be
used in clinical, laboratory and instrument reprocessing areas
as it is not impervious.
Computer keyboards in the dental operatory may harbour
microorganisms such as Staphylococcus aureus (MRSA)
and should be covered where possible in treatment areas,
and regularly cleaned in non-treatment areas. A number
of keyboards are available with flat surfaces which can be
wiped over with detergent or with alcohol-impregnated
wipes between patient appointments. Patient notes written
by hand or electronically must follow a protocol which
prevents environmental contamination of the hard copy
notes or computer keyboard. Traditional computer keyboards
are not waterproof and are likely to be damaged by repeated
application of detergent.
Eating and common room areas for dental staff must be
separate from patient treatment areas and the dental
laboratory and conform to work health and safety
regulations.
Lunchroom crockery must not be washed in the handwash
sinks or in instrument wash basins. Food must not be
stored in a refrigerator with dental materials, sealed clinical
specimens or medical products such as drugs or blood
because of the risks of cross-contamination.
Cleaning the environment
Floors, walls and curtains pose minimal risk of disease
transmission in a dental practice; nevertheless, these surfaces
must be maintained in a clean and hygienic condition. State
and territory public health regulations require that premises
be kept clean and hygienic.
Environmental surfaces such as bench tops outside the
contaminated zone must be cleaned weekly using detergent
and water. The practice should develop a schedule to ensure
areas including floors, window sills, door handles, and
telephone handsets are cleaned weekly. Likewise, a schedule
should also be developed for cleaning solid surfaces in the
waiting room. Walls, blinds and window curtains in patient
care areas must be cleaned when they are visibly dusty
or soiled.
The dental operatory and instrument reprocessing rooms
must have clearly defied clean and contaminated zones.
The contaminated zone is the area which becomes
contaminated by splashes and droplets originating from the
patient’s mouth (typically within a distance of one metre).
Aerosols generated from patient care may extend further
than splashed material (up to approximately 1.8 metres).
Inanimate objects such as toys act as fomites and can
spread infections through indirect contact. For this
reason, it is prudent to wipe down the hard surfaces of
toys in reception and waiting areas on a periodic basis
using detergent impregnated wipes designed for use on
clinical hard surfaces, to reduce the levels of transient
microorganisms.
Page 12 | Guidelines for Infection Control
Cleaning methods must avoid the generation of aerosols.
Damp dusting, dust-retaining mops and vacuum cleaners
with air filtration of the exhaust are recommended. Brooms
must not be used in clinical areas as these disperse dust and
bacteria into the air.
Mops and cloths must be cleaned after use and allowed to
dry before reuse. Alternatively single-use, disposable mop
heads or cloths may be used.
Treatment areas
Routine cleaning of the contaminated zone within
the dental operatory is necessary to maintain a safe
environment because deposits of dust, soil and microbes
on environmental surfaces can transmit infection. Surfaces
of dental units must be impervious as they may become
contaminated with potentially infective material. Work
surfaces and bench tops in treatment areas must be non-
porous, impervious to water, smooth without crevices and
have sealed joins to facilitate cleaning and prevent the
accumulation of contaminated matter. Working surfaces in
the contaminated zone must be cleaned after every patient
by wiping the surface with a neutral detergent. Standard
precautions (including wearing of personal protective
equipment as applicable) must be implemented when
cleaning these surfaces.
A neutral detergent and warm water solution or
commercially packaged pre-moistened, neutral detergent
wipes should be used for all routine and general cleaning.
Neutral pH detergents are best for environmental cleaning
because they are less likely than acid or alkaline detergents
to damage metals such a stainless steel or to cause skin
irritation.
Neutral detergents also leave little residue on surfaces.
Fresh cleaning solutions of detergent should be prepared
daily as instructed by the manufacturer. Containers for
these fresh solutions should be emptied, washed and dried
overnight prior to refilling for subsequent use.
Written protocols for cleaning the practice must be
prepared, including methods and frequency.
General work surfaces in the dental operatory outside the
contaminated zone must be cleaned after each session or
when they become visibly soiled. Sinks and wash basins must
be cleaned at least daily, or more frequently as appropriate.
Usually, spittoons cannot be removed for cleaning or
sterilising. They are not classified as instruments as they do
not contact any part of the body. The spittoon should be
cleaned after each patient by wiping with neutral detergent
using disposable paper towels.
Guidelines for Infection Control | Page 13
The contaminated zone boundaries should be clearly defined,
because this has implications for surface management and
for the placement of equipment. The goal during dental
treatment is to contain contamination within this zone,
both by determining what is touched and where the spread
of droplets, splash and splatter will occur.
Reducing the extent of contamination of the dental operatory
can be achieved in part by use of rubber dam, pre-procedural
antiseptic mouthrinses, high volume evacuation and correct
patient positioning. Rubber dam minimises the spread of
blood or saliva. When rubber dam is not applied, high
volume aspiration becomes essential.
All surfaces and items within the contaminated zone must
be deemed contaminated by the treatment in progress.
These surfaces must be cleaned and the items in the zone
disposed of, decontaminated, or cleaned and sterilised before
commencing treatment of the next patient. Clinical contact
surfaces in the contaminated zone not barrier protected must
be cleaned after each patient.
Note: Instruments placed into the contaminated zone for a
treatment session but not used during the session must be
regarded as contaminated. For this reason all bulk supplies
such as opened boxes of gloves, cotton rolls or gauze must
be stored outside the contaminated zone and protected from
contamination from splashes and aerosols.
For equipment that is difficult to clean, a protective covering
such as a plastic wrap may be necessary. Items where barrier
protection may be required include:
• the operating light handle and its hand operated
switch, the X-ray head, tubing for suction, triplex
syringe, and instrument cradles;
• the polymerising light, intraoral camera and fibre-
optic illuminator; and
• the bracket table and handle.
Any surface barriers used on such surfaces should be
disposed of after each patient treatment, and a new barrier
placed in general waste.
In an operatory utilised by multiple dental practitioners,
and where dental assistants are not routinely assigned to
the same operatory, use of barriers may be preferable.
However, if barriers are not used, a documented cleaning
protocol should be followed.
C. Infection control strategies within the
contaminated zone
1. Clean and contaminated zones
Within the dental surgery, clean and contaminated zones
must be clearly demarcated. Clean areas include those
surfaces and drawers where clean, disinfected or sterilised
instruments are stored and never come in contact with
contaminated instruments or equipment. All dental staff
must understand the purpose of and requirements within
each zone, and adhere to the outlined protocols. A system of
zoning aids and simplifies the decontamination process.
Dental practitioners and clinical support staff should not
bring personal effects, changes of clothing or bags into
clinical (patient treatment) areas where cross-contamination
is likely to occur.
It is recommended, where possible, that materials such
as cotton rolls, dental floss, gingival retraction cord and
restorative materials should be pre-dispensed from bulk
supplies that are kept in drawers or containers which keep
these bulk supplies free of contamination from splashes
or aerosols.
However, if additional instruments and materials have to
be retrieved from outside the contaminated zone during a
patient treatment, it must be by a method that does not
contaminate other instruments or materials in the drawers.
The options include:
• open drawers by elbow touch; retrieve instruments
and materials with a no-touch technique such as
transfer tweezers; use over-gloves or single-use
barriers on drawer handles. If transfer tweezers
are used, these must be kept separate from other
instruments;
• gloves must be removed and hands decontaminated
with ABHR before dispensing additional materials.
When moving from the contaminated zone to a clean zone
to touch non-clinical items without a barrier, gloves must
be removed and hands washed or decontaminated with
ABHR before touching the item. The individual must then
perform hand hygiene (e.g. with ABHR) and re-glove before
re-entering the contaminated zone.
Cartridges of local anaesthetic must be stored appropriately
to prevent environmental contamination by aerosols,
splatter and droplets generated by clinical patient care.
Cartridges should be kept in their individual bubble packs
until use to protect them from contamination by dust,
aerosols, and droplets. They must never be stored loose out
of their blister packaging in cardboard containers as these
absorb water and cannot be cleaned.
Page 14 | Guidelines for Infection Control
Containers of medicaments, including topical anaesthetic
tubes or jars and endodontic medicaments must be kept
free of environmental contamination. Once used, glass local
anaesthetic cartridges or carpules are classified as sharps
and must be disposed as sharps waste. If they are polymer,
they must be emptied of all remaining local anaesthetic
solution, into the sink if permitted by local water board
regulations, before being disposed of into the regular waste.
Polymer carpules can also be placed into the sharps waste
if preferred.
2. Waterlines and water quality
Most dental unit waterlines contain biofilm, which acts
as a reservoir of microbial contamination. Biofilm in dental
unit waterlines may be a source of known pathogens
(e.g. Pseudomonas aeruginosa, non-tuberculous
mycobacteria, and Legionella spp). Waterlines must
be cleaned and disinfected in accordance with the
manufacturer’s instructions. All waterlines must be fitted
with non-return (anti-retraction) valves to help prevent
retrograde contamination of the lines by fluids from the
oral cavity.
An independent water supply can help to reduce the
accumulation of biofilm. The manufacturer’s directions
should be followed for appropriate methods to maintain
the recommended quality of dental water and for
monitoring water quality. Biofilm levels in dental equipment
can be minimised by using a range of measures, including
water treatments using ozonation or electrochemical
activation, chemical dosing of water (e.g. with hydrogen
peroxide, peroxygen compounds, silver ions, or nanoparticle
silver), flushing lines (e.g. triple syringe and handpieces)
after each patient use, and flushing waterlines at the
start of the day to reduce overnight or weekend biofilm
accumulation. This is particularly important after periods
of non-use (such as vacations and long weekends).
Flushing each day has been shown to reduce levels of
bacteria in dental unit waterlines.7, 8
Air and waterlines from any device connected to the
dental water system that enter the patient’s mouth
(e.g. handpieces, ultrasonic scalers, and air/water syringes)
should be flushed for a minimum of two minutes at the
start of the day and for 30 seconds between patients.
Water quality
Sterile irrigants such as sterile water or sterile saline as
a coolant are required for surgical procedures such as
dentoalveolar surgery, endodontic surgery, and dental
implant placement.
Further information on dental unit waterlines and water
quality for sterilisers can be found in the ADA’s Practical
Guide to Infection Control.
3. Single-use items
Single ‘one patient’ use non-sterile items, including
disposable triple syringe tips, plastic low and high velocity
evacuator tips, prophylaxis cups, micro-brushes, plastic
Dappen dishes, and disposable impression trays must not
be reprocessed and reused on another patient, but must
be discarded after use. For common simple triple syringe
designs (DCI or A-dec type), disposable triple syringe tips are
preferred due to efficiency reasons (difficulty of cleaning and
challenge to air removal and steam penetration).
Ultrasonic cleaning does not remove all bioburden from
within the lumen of metal triple syringe tips, so accumulation
of internal bioburden over time could potentially occur.
7
Cobb CM, Martel CR, McKnight SA3rd, Pasley-Mowry C, Ferguson BL, Williams K. How does time-dependent dental unit waterline flushing
affect planktonic bacteria levels? J Dent Educ. 2002;66(4):549-55.
8
Watanabe E, Agostinho AM, Matsumoto W, Ito I. Dental unit water: bacterial decontamination of old and new dental units by flushing water.
Int J Dent Hyg. 2008;6(1):56-62.
9
CDC (2003) Guidelines for Infection Control in Dental Health-Care Settings, page 29
The organisms which grow in waterline biofilms are
environmental in origin, and are found in lakes, rivers and
other water sources. They flourish in the waterlines of a
dental unit because lines to the handpieces, triplex syringe
and ultrasonic scaler are small in diameter, and hence
have very slow flow rates and large surface area to volume
ratios. The cup fill and spittoon lines are larger in diameter
and pass more water at higher flow rates, and thus tend to
show lower levels of biofilm than those lines with small
diameter tubing.
In line with the Australian drinking water quality guidelines,
water for tooth irrigation during cavity preparation and
for ultrasonic scaling should be of no less than potable
standard NHMRC Australian Drinking Water Guidelines.
The number of bacteria in water used as a coolant/irrigant
for non-surgical dental procedures should be less than 500
CFU/mL, since this is a widely used international limit for
safe drinking water.9
When treating immunocompromised
patients, it is recommended that water from dental unit
waterlines contain less than 200 CFU/mL. Bacterial levels
can be tested using commercially available test strips or
through commercial microbiology laboratories.
Levels of microorganisms in dental unit waterlines can be
assessed using commercial test kits. Typically, these are a
growth medium which is inoculated with a water sample
and then incubated at room temperature for up to seven
days, after which time colony counts are made.
Guidelines for Infection Control | Page 15
Moreover, metal triple syringes need to be sterilised in a
pre-vacuum cycle to ensure air removal and steam penetration.
Many practices find disposable plastic tips for DCI/A-dec triple
syringes easier to use and more convenient than metal syringe
tips thus enhancing infection control.
Very small and/or sharp instruments are difficult to clean
and should be considered single-use. Such instruments must
not be reused unless a validated and safe cleaning process is
employed. This is very relevant to matrix bands, stainless steel
endodontic files, reamers and broaches. These items are to be
considered single-use items as there is currently no cleaning
method validated as being effective in removing organic
material from these items.
Single ‘one patient’ use sterile items should be used whenever
indicated by the clinical situation. These items include, but are
not limited to, local anaesthetic needles, cartridges, sutures
and scalpel blades.
Dental local anaesthetic solution and needles must be
sterile at the time of use and are only for single-patient use.
Used local anaesthetic cartridges must be discarded after
each patient. Similarly, suture materials, suture needles
and scalpel blades must be used for one patient and then
disposed of immediately into an approved sharps container.
4. Matrix bands
5. Burs
6. Implant drills
Further information on implant drills can be found in the
ADA’s Practical Guide to Infection Control.
Matrix bands contacting the gingiva often become
contaminated with blood during use and if pushed down
hard into the tissues will draw blood. A matrix band is not a
surgical blade and it is not necessary before use to sterilise
plain stainless steel matrix bands. A wide range of matrix
bands are now available including some combined with
wedges for interdental protection which are not suitable
for steam sterilising because of heat sensitive components
(e.g. combination of a steel plate and a plastic wedge).
Other items used interdentally, such as wooden or plastic
wedges, interdental brushes and dental floss are not
supplied sterile. There is no evidence base around infections
arising from these items or from contamination on matrix
bands, dental floss or interdental brushes.
According to AS/NZS 4815, items to be reused must
be free of corrosion and suitable for use in order to be
reprocessed.
Stainless steel burs which become blunt and corrode
after multiple uses must be discarded into the sharps
waste. They are also difficult to clean. Therefore, staff must
look for the tell-tale signs of wear and corrosion as these
burs are reprocessed.
Typically, this is seen after the third or fourth cycle of use,
particularly when a corrosion inhibitor is not used during
reprocessing. Dental practices may use lower cost stainless
steel burs as single-use items to eliminate the need to clean
and inspect them. This ensures burs when used are always
sharp. Without special lighting and magnification, it is
not possible to properly clean and inspect burs with small
cutting heads.
Most diamond burs are designed for reprocessing.
The resin carrier for the diamond does degrade with
multiple steriliser cycles. Some brands of diamond burs
chrome cobalt alloy as a matrix for the diamond particles
which are very long lasting.
Most surgical burs for dento-alveolar surgery are designed
for reprocessing, and are made of materials such as
tungsten carbide that do not degrade under steam
sterilising. Likewise, silicon nitride burs are also designed
for reprocessing.
Further information on implant drills can be found in the
ADA’s Practical Guide to Infection Control.
The manufacturer’s advice is important, as the materials
used in implant drills vary, with some being made from
stainless steel and intended for reuse, and others for single-
use only. For stainless steel burs, reuse may be possible
if appropriately cared for, undamaged and correctly
reprocessed to be free of contamination.
Page 16 | Guidelines for Infection Control
Contaminated instruments can transmit infections between
patients and it is essential that instruments are correctly
reprocessed between each patient. The type of instrument and
its intended use will determine the method of reprocessing
and, as a general rule, if an instrument cannot be cleaned it
cannot be safely reprocessed. Reprocessing instruments must
be in accordance with AS/NZS 4815 and/or AS/NZS 4187.
1. Categories of instruments: infection risk
relative to instrument use10
Contaminated instruments can transmit infections to patients
during clinical procedures. The risk of this happening is
related to the site of use. The intended use of the instrument
dictates the amount of reprocessing or preparation required
for reusable instruments and equipment. The Spaulding
classification describes three instrument/risk categories (critical,
semi-critical and non-critical), each of which has specific
reprocessing requirements.
Equipment and instruments used in the treatment of
mucosal lesions or diseased soft tissue and that come in
direct contact with mucosa and gingiva or blood must be
single-use disposable or cleaned and re-sterilised after each
patient. Examples are electrosurgery, cryotherapy and related
devices and tips.
D. Instrument reprocessing
10
Based on the Spaulding classification system as described in section B4.1.1 of the 2010 NHMRC Guidelines.
Critical Item: Where there is entry or penetration
into sterile tissue, cavity or bloodstream (e.g.
surgical dental procedures such as the removal of
a fully impacted tooth, extraction, and endodontic
procedures on vital pulp tissue).
Examples: dental forceps and elevators; flap
retractors and surgical burs; instruments used
in the placement of implants; implantable items
including mini implants; and surgical dental
handpieces.
1. These instruments must be sterile at the time of
use and must be either ‘single-use disposable’
or capable of being steam sterilised.
2. Critical items must be used immediately after
sterilisation or bagged prior to sterilisation
and kept stored in bags until used. Instruments
stored in bags found to be damaged must be
re-sterilised before use.
3. It is recommended to use batch control
identification for these surgical instruments.
Non-critical Item: Where there is contact with
intact skin (lowest risk).
Examples: prosthetic gauges and measuring
devices; face bows; protective eyewear; bib chain
and Dappens dishes; and Willis gauges. Generally,
cleaning alone with detergent and water is
sufficient but in some cases thermal disinfection
with heat and water is appropriate. After
processing, these instruments should be stored
in the same way as semi-critical instruments to
prevent environmental contamination prior to use.
Semi-critical Item: Where there is contact with
intact non-sterile mucosa or non-intact skin.
Examples: mouth mirrors; restorative instruments;
dental tweezers and probes; metal impression
trays; and other noncritical items when used
occasionally in the mouth (e.g. Le Cron carver).
1. Instruments must be sterilised where possible
and when not possible a barrier must be placed
(e.g. curing light tip).
2. Instruments should be ‘single-use disposable’
or sterilised after use.
3. After processing, semi-critical instruments
should be stored in a way to prevent
contamination prior to use by being kept
bagged in closed drawers or in dedicated
containers such as instrument cassettes.
4. Instruments used in semi-critical procedures
should, where possible, be sterilised between
patients but do not need batch control
identification and are not required to be sterile
at the point of use.
5. In some rare instances thermal disinfection
using heat and water is acceptable and
professional judgement needs to be exercised
(e.g. thermal disinfection of denture polishing
buffs may be appropriate as these are unlikely
to be contaminated with blood).
Guidelines for Infection Control | Page 17
2. Instrument reprocessing area and
workflow
Reprocessing is a term which includes all steps necessary
to make a contaminated reusable device ready for its
intended use. These steps may include cleaning, functional
testing, packaging, labelling, disinfection and sterilisation.
Part of the dental premises must be designated as the
reprocessing area for reusable instruments (including
cleaning, packaging and sterilising) and not used for any
other purpose. Ideally, this should be a dedicated room
separate from the treatment room(s) but if not possible
because of limited space, instrument reprocessing should
occur well clear of the contaminated zone with good
workflow processes established and where there is minimal
risk of aerosol contamination of the reprocessing area.
The cleaning process should flow in one direction, from
contaminated to clean. If instrument washing must take
place in the clinical or laboratory area due to limitations
of space, then contaminated areas and instrument washing
sinks must be clearly designated. Instrument flow must
be in one direction: from contaminated through to clean.
The instrument reprocessing area must be appropriate
in layout and size for the volume of instruments being
reprocessed.
To minimise particulate contamination and bio-
burden (pathogenic bacteria, fungi and viruses),
the principles of environmental control need to be
observed. The reprocessing area must be divided
into distinct areas for:
• receiving, cleaning and decontamination;
• preparation and packaging;
• sterilisation; and
• storage.
Processed instruments must not be stored in
an area where contaminated instruments are
held or cleaned or where there is a possibility of
contamination from organisms carried in droplets
or aerosols.
Design of the reprocessing area
Following are design features for the reprocessing area
which will facilitate successful infection control:
• instrument flow in one direction – from dirty to
clean;
• good lighting to minimise the risk of sharps injury
and enable inspection of cleaned instruments;
• efficient ventilation;
• non-slip water-impervious flooring that is readily
cleanable;
• smooth work surfaces without crevices made
of non-porous materials such as stainless steel
or laminate to facilitate cleaning. There must be
no inaccessible areas where moisture or soil can
accumulate;
• work benches of a standard height and storage
cupboards located at heights to minimise bending
over or stretching overhead;
• sinks must be deep enough and taps provided with
anti-splash devices. Ideally there should be several
sinks – one for handwashing and one for manually
washing contaminated instruments;
• both hot and cold water taps should ideally be
non-touch or electronic in operation and liquid
handwash dispensers should be operated by elbow,
knee or foot;
• sufficient drawers, cupboards and shelves to keep
work benches as clutter-free as possible and to
facilitate temporary storage of sterilised packages
as well as general items such as labelling guns,
logbooks, cleaning agents and self-sealing bags;
• sufficient bench space for drying and packaging
areas to enable efficient work practices; and
• a cooling area for sterile items awaiting storage;
essential to prevent damage to packs.
Trays of instruments, when removed from the steam
steriliser, should be placed on racks and not directly on the
bench to prevent damage from water condensation under
the cooling packages.
Page 18 | Guidelines for Infection Control
3. Transfer of contaminated instruments
and sharps
Instruments should be carried to the sterilising area in a
cassette or in a container that is preferably lidded and
puncture-proof, to minimise handling and prevent the
potential for a penetrating injury if the container is dropped.
A systematic approach to the decontamination of
instruments after use will ensure dirty instruments are
segregated from clean items. Contaminated instruments
should be carried with gloved hands to the cleaning area
and placed on the bench in the ‘contaminated zone’ of the
sterilising room. Gloves must then be taken off and hands
washed. Once the cleaning process commences, heavy-duty
utility gloves must be worn.
Remember: instruments must pass in one direction
only, from contaminated to clean.
4. Cleaning
Used dental instruments are often heavily contaminated
with blood and saliva unless pre-cleaned by wiping at the
chairside. Pre-cleaning is strongly recommended to improve
the safety and effectiveness of instrument reprocessing.
Dental instruments and devices contaminated with blood,
saliva, cements and other contaminants must be treated
to prevent substances drying on them. This will reduce
the need for intensive cleaning by hand at a later stage.
It is recommended that gross soil be removed from
instruments by wiping them at the chairside onto an
adhesive-backed sponge or dampened gauze on the
bracket table using a one-handed method to prevent the
risk of sharps injury during the wiping action. Alternatively,
if they are unable to be cleaned immediately, the instruments
may be soaked in detergent or an enzymatic agent to
prevent hardening of residue.
Instruments must be completely cleaned before being
disinfected or sterilised as the presence of organic material
left on instruments/equipment may prevent steam
penetration during sterilisation.
Cleaning significantly reduces the number of microorganisms
that need to be killed during sterilisation or disinfection.
In addition, removing organic material lessens the chance
of microorganisms multiplying on the instruments before
reprocessing commences. If saliva dries and coagulates –
particularly if blood is present or if hot water is used for
cleaning – it can entrap the organisms inside the mass formed
and inhibit penetration of the sterilising/disinfecting agent.
When potential disease-producing organisms are killed,
released endotoxins may remain, causing fevers in patients
if introduced into cuts or wounds. Similarly, dislodged soil
and foreign particles, even if sterile, can produce severe
complications such as granulomas if they enter a cut in the
skin or ulcer in a breach of the oral epithelium.
Clinical support staff cleaning and reprocessing instruments
must be provided with formal training in the relevant
procedures.
These staff must use heavy-duty utility (puncture and
chemical-resistant) gloves, and wear eye protection/face
shield and a mask. A waterproof/fluid-resistant gown/apron
is also recommended. Cleaning techniques should aim to
avoid spraying liquids into the air. Likewise, the lid should
be kept on the ultrasonic cleaner when in use to prevent
dispersion of aerosols and droplets of fluids.
Splashes of cleaning agents on a person’s skin must be
washed quickly with clean water and then treated in
accordance with the manufacturer’s instructions.
Instruments can be cleaned either by hand or mechanically
(in either an ultrasonic bath or instrument washer/disinfector).
Automated mechanical cleaning is preferred to manual
cleaning as it is more efficient, reduces the risk of exposure
to blood and reduces the risk of penetrating skin injuries from
sharp or pointed instruments.11
Following either manual or mechanical cleaning, instruments
should be checked visually under good lighting to ensure
all soil/contaminants are removed. Damaged or rusted
instruments must be repaired or discarded, and those
with visible residue soil/contamination must be re-cleaned.
If the item is not clean the sterilisation process will be
compromised.
11
Miller CH, Tan CM, Beiswanger MA, Gaines DJ, Setcos JC, Palenik CJ. “Cleaning dental instruments: measuring the effectiveness of an
instrument washer/disinfector” Am J Dent 2000;13 (1):39-43.
For pre-cleaning, use a mildly alkaline detergent solution.
Mildly alkaline detergents are more suitable for dissolving
proteinaceous materials than neutral detergents, but are
more irritating to skin should accidental splashing occur.
Under AS/NZS 4815, using enzymatic agents as a routine
measure in instrument reprocessing is discouraged because
of skin irritancy and other workplace health and safety
issues. In dental practice, such agents are used in approved
and validated protocols reprocessing rotary nickel-titanium
for endodontic files. The use of these agents on an
occasional basis for soaking surgical instruments before
mechanical cleaning is acceptable.
The use of manual cleaning is discouraged where
mechanical cleaning can be used for items, i.e. no hand
scrubbing before instruments are placed into an ultrasonic
cleaner or instrument washer/thermal disinfector.